JP2011186410A - Liquid crystal display device and manufacturing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display device with high transmittance. <P>SOLUTION: The liquid crystal display device is provided with: a first substrate, a second substrate; and a liquid crystal layer enclosed between the first substrate and the second substrate; and multiple pixels with first electrode and second electrode one of which is a pixel electrode. The pair of electrodes is installed on either the first substrate or the second substrate, and a high molecule structure is formed between the pixel electrodes adjacent to each other. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device and a manufacturing method thereof.

  A liquid crystal display device is a display device having a liquid crystal display panel in which a liquid crystal layer is provided between a pair of substrates. For example, the liquid crystal display device is widely used as a liquid crystal display for a liquid crystal television, a personal computer, a liquid crystal display for a mobile phone terminal, or the like. Yes.

  This type of liquid crystal display device is a display device in which a display area of a liquid crystal display panel is a set of a plurality of pixels, and images and videos such as letters, numbers, figures, and pictures are displayed by the plurality of pixels (dots). . Such a display method is generally called a dot matrix method.

  The dot matrix method is classified into a simple matrix type (sometimes called a passive matrix type) and an active matrix type depending on a pixel driving method. The simple matrix type is a type in which a predetermined pixel is driven by selectively applying a voltage to a pixel forming electrode formed on each substrate. On the other hand, the active matrix type is a type in which an active element for pixel selection (sometimes called a switching element) is formed on one substrate, and a predetermined pixel is driven by turning on / off the active element. In particular, the latter active matrix type has an excellent performance such as a contrast performance and a high-speed display performance, and therefore has become a mainstream pixel driving method in a liquid crystal display device.

  As an operation mode of the liquid crystal layer in this type of liquid crystal display device, for example, a TN (Twisted Nematic) mode, an STN (Super Twisted Nematic) mode, a VA (Vertical Aligned IP) mode, an OCB (Optically Compensated IP) mode, and the like. (In-Plane Switching) mode, FFS (Fringe Field Switching) mode, and the like.

  In particular, large liquid crystal display devices such as liquid crystal televisions are required to have high contrast and high viewing angle, and an IPS mode and an FFS mode have been developed for this purpose. These needs are also required for small liquid crystal display devices such as mobile phones, and the development of products in IPS mode and FFS mode is accelerated.

  In addition, in recent mobile phone terminals and car navigation systems, for example, many of them are equipped with functions for viewing TV broadcasts and playing videos, and even in small liquid crystal display devices used in these portable electronic devices, Power saving is a new need for long-term use.

  Patent Document 1 includes a first substrate having a plurality of pixel switching elements and a plurality of pixel electrodes, and a second substrate on which a counter electrode is formed. A liquid crystal device is described in which a polymer network is formed at the boundary between adjacent pixels between two substrates.

JP 2001-209026 A

  Incidentally, in order to achieve power saving in the IPS mode and FFS mode liquid crystal display devices, it is necessary to improve the transmittance of the pixels. In order to improve the transmittance of the pixel, for example, it is effective to increase the size of the pixel electrode itself. However, when the size of the pixel electrode is increased, the alignment of the liquid crystal of one of the adjacent pixels also affects the alignment of the liquid crystal of the other pixel, so there is a limit to increasing the size of the pixel electrode. It was.

  Another method for improving the transmittance of pixels is to suppress disclination. However, the actual situation is that there is no way to sufficiently avoid disclination.

  An object of the present invention is to provide a liquid crystal display device having a high transmittance and a method for manufacturing the same. The novel features of the present invention will become apparent from the description of this specification and attached drawings.

  The outline of typical inventions among the inventions disclosed in the present application will be described as follows.

  A first substrate, a second substrate, and a liquid crystal layer sealed between the first substrate and the second substrate, wherein one of the first electrode and the second electrode is a pixel electrode A liquid crystal display device in which a plurality of pixels having two electrodes are provided, wherein the first electrode and the second electrode are provided on one of the first substrate and the second substrate, and are adjacent to each other. A liquid crystal display device, wherein a polymer structure is formed between pixel electrodes.

  Manufacture of a liquid crystal display device having a liquid crystal layer sealed between a first substrate and a second substrate, and a plurality of pixels each having a first electrode and a second electrode, each of which is a pixel electrode A method comprising: encapsulating the liquid crystal layer between the first substrate and the second substrate, wherein in the step, a liquid crystal composition containing a base liquid crystal and a polymerizable monomer used for the liquid crystal layer An object is sealed between the first substrate and the second substrate, and a polymerization initiator is localized between the adjacent pixel electrodes, and then the polymerizable monomer is polymerized to be adjacent. A method of manufacturing a liquid crystal display device, comprising forming a polymer structure between the pixel electrodes.

  ADVANTAGE OF THE INVENTION According to this invention, the liquid crystal display device which has a high transmittance | permeability, and its manufacturing method can be provided.

It is explanatory drawing which shows an example of the main structures in planar view of the liquid crystal display panel which concerns on this invention. It is description which shows an example of the cross section of the liquid crystal display panel in the position of the II-II line | wire of FIG. It is explanatory drawing which shows typically the arrangement | positioning about an example of the main structures in planar view of the TFT substrate which concerns on this invention. It is explanatory drawing which shows typically the arrangement | positioning about an example of the main structures in the planar view of the color filter substrate which concerns on this invention. FIG. 5 is an explanatory diagram showing an example of a cross section of a liquid crystal display panel and an arrangement of polymer structures at the position of the VV line in FIGS. 3 and 4. FIG. 5 is an explanatory diagram showing another example of the cross section of the liquid crystal display panel and the arrangement of the polymer structure at the position of the VV line in FIGS. 3 and 4. It is explanatory drawing which shows an example of arrangement | positioning of the polymer structure formed in the color filter substrate in planar view. It is explanatory drawing which shows the other example of arrangement | positioning of the polymer structure formed in the color filter substrate by planar view. It is explanatory drawing which shows the further another example of arrangement | positioning of the polymer structure formed in the color filter substrate in planar view. It is explanatory drawing which shows the further another example of arrangement | positioning of the polymer structure formed in the color filter substrate in planar view. FIG. 5 is an explanatory diagram showing still another example of the cross section of the liquid crystal display panel and the arrangement of the polymer structure at the position of the VV line in FIGS. 3 and 4. FIG. 5 is an explanatory diagram showing still another example of the cross section of the liquid crystal display panel and the arrangement of the polymer structure at the position of the VV line in FIGS. 3 and 4. FIG. 5 is an explanatory diagram showing still another example of the cross section of the liquid crystal display panel and the arrangement of the polymer structure at the position of the VV line in FIGS. 3 and 4. FIG. 5 is an explanatory diagram showing still another example of the cross section of the liquid crystal display panel and the arrangement of the polymer structure at the position of the VV line in FIGS. 3 and 4. It is explanatory drawing which expands and shows an example of arrangement | positioning of the polymer structure in the edge part area | region of the pixel electrode enclosed with the broken line of FIG. It is explanatory drawing which shows an example of the arrangement | positioning of the cross section of the liquid crystal display panel cut | disconnected in the edge part area | region of FIG. 11A, and a polymer structure. It is explanatory drawing which shows an example of arrangement | positioning of the main structure in planar view of the TFT substrate which concerns on this invention, and an edge part area | region of a pixel electrode.

  Hereinafter, the present invention will be described in detail together with embodiments with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof is omitted.

  FIG. 1 to FIG. 12 are schematic views for explaining a schematic configuration of a main part of a liquid crystal display device according to the present invention.

  FIG. 1 is a schematic plan view showing an example of a planar configuration of a liquid crystal display panel according to the present invention. FIG. 2 is a schematic cross-sectional view showing an example of a cross-sectional configuration at the position of line II-II in FIG. FIG. 3 is a schematic plan view showing an example of a planar configuration of the TFT substrate. FIG. 4 is a schematic plan view illustrating an example of a planar configuration of the color filter substrate. 5 to 10 are cross-sectional views or plan views showing an example of a cross-sectional configuration and a polymer structure arranging method at the positions of the VV line in FIG. 3 and the VV line in FIG. 4. 11A and 11B are a plan view and a cross-sectional view showing an example of a method for arranging the polymer structure at the electrode end. FIG. 12 is a plan view showing an example of a method of arranging the polymer structure at the electrode end.

  In this specification, as an example of the liquid crystal display device according to the present invention, a small liquid crystal display device used for a mobile phone terminal or the like is given. In addition, the present invention relates to the configuration of a liquid crystal display panel among liquid crystal display devices. Therefore, in this specification, the structure of a liquid crystal display panel and the manufacturing method thereof are demonstrated among the liquid crystal display devices which concern on this invention.

  The basic configuration of the liquid crystal display panel according to the present invention may be the same as the conventional one. Therefore, in the present specification, the configuration of the characteristic part of the liquid crystal display panel according to the present invention and the manufacturing method thereof will be mainly described, and a specific description regarding the configuration and the manufacturing method similar to those of the conventional one may be omitted. . The liquid crystal display panel is assumed to be an active matrix type.

  The liquid crystal display panel according to the present invention includes, for example, a TFT substrate 1 (first substrate), a color filter substrate 2 (second substrate), a liquid crystal layer 3, a sealing material 4a, as shown in FIGS. 4b, a first polarizing plate 5, a second polarizing plate 6, and a polymer structure 7. The liquid crystal display panel includes a plurality of pixels each having a first electrode and a second electrode, one of which is a pixel electrode. That is, each of the plurality of pixels has a first electrode and a second electrode for applying an electric field to the liquid crystal layer 3, and one of the first electrode and the second electrode is a pixel electrode. is there.

  The TFT substrate 1 includes a first insulating substrate 101, a first thin film stack 102, and a first alignment film 103. The first insulating substrate 101 is a transparent insulating substrate such as a glass substrate, for example. The first thin film stack 102 includes, for example, a scanning signal line, a video signal line, a TFT element, a pixel electrode, and a plurality of insulating layers. The first alignment film 103 is made of, for example, a polyimide film whose surface (interface with the liquid crystal layer 3) is subjected to an alignment process such as a rubbing process. Note that the first alignment film 103 may be subjected to a photo-alignment process.

  The color filter substrate 2 includes a second insulating substrate 201, a second thin film stack 202, and a second alignment film 203. The second insulating substrate 201 is a transparent insulating substrate such as a glass substrate. The second thin film stack 202 includes, for example, a black matrix, a color filter, and a planarization layer. The second alignment film 203 is made of, for example, a polyimide film whose surface (interface with the liquid crystal layer 3) is subjected to an alignment process such as a rubbing process. Note that the second alignment film 203 may be subjected to a photo-alignment process.

  In the liquid crystal display panel, as shown in FIGS. 1 and 2, a liquid crystal layer 3 is provided between the TFT substrate 1 and the color filter substrate 2. The TFT substrate 1 and the color filter substrate 2 are bonded together with an annular sealing material 4a surrounding the display area DA. The sealing material 4a has an injection port for injecting a liquid crystal composition used as the liquid crystal layer 3, and the injection port is sealed with the sealing material 4b. That is, the liquid crystal layer 3 is sealed between the TFT substrate 1 and the color filter substrate 2 by the sealing materials 4a and 4b. Although not shown, a spacer is provided between the TFT substrate 1 and the color filter substrate 2, for example, to make the thickness of the liquid crystal layer 3 uniform in each pixel.

  In the liquid crystal display panel according to the present invention, a polymer structure 7 is provided between the TFT substrate 1 and the color filter substrate 2 in addition to the liquid crystal layer 3 and the spacer. This polymer structure 7 is for preventing the influence of orientation between adjacent pixels. That is, the polymer structure 7 is provided in order to reduce or avoid the influence of the liquid crystal orientation of one pixel among the adjacent pixels on the liquid crystal orientation of the other pixel.

  The polymer structure 7 is formed between adjacent pixel electrodes 8. In the example shown in FIG. 2, the polymer structure 7 is provided in a region corresponding to the black matrix 13 of the color filter substrate 2 (a region below the black matrix 13). That is, the polymer structure 7 is formed in a region overlapping with the black matrix. The polymer structure 7 is provided, for example, at all pixel boundaries included in the display area DA. Note that the dimension Px in FIG. 2 indicates the dimension of one pixel in the x-axis direction.

  Hereinafter, the structure of each pixel and the shape and size of the polymer structure 7 will be specifically described with reference to FIGS.

  As an example of the configuration of the pixel in the liquid crystal display panel according to the present invention, the configuration of the pixel in the FFS mode, which is one of the IPS modes, will be given. In the FFS mode liquid crystal display panel, as in the IPS mode, the first electrode and the second electrode are provided on one of the first substrate and the second substrate. That is, in the example shown in FIGS. 1 and 2, both the pixel electrode 8 and the common electrode 9 are provided on the TFT substrate 1 (more specifically, the first thin film stack 102).

  As shown in FIG. 3, the liquid crystal display panel includes scanning signal lines 10 and video signal lines 11. A distance Px between two adjacent video signal lines 11 is a dimension in the x-axis direction of one pixel. A distance Py between two adjacent scanning signal lines 10 is a dimension of one pixel in the y-axis direction. FIG. 3 schematically shows the configuration of one pixel PC and the vicinity thereof in plan view, and the relationship between the dimension in the x-axis direction and the dimension in the y-axis direction is the same as that in an actual liquid crystal display device. Does not necessarily match.

  Each pixel in the liquid crystal display panel includes, for example, a gate electrode connected to one scanning signal line 10, a first source / drain electrode connected to one video signal line 11, and a pixel electrode. 8 includes a TFT (thin film transistor) element 12 including a second source / drain electrode connected to 8.

  As shown in FIG. 3, in each pixel, the region where the liquid crystal is driven depends on the size of the pixel electrode 8 and the common electrode 9. Therefore, it is understood that increasing the size of these electrode groups is effective for improving the transmittance in the liquid crystal display device. However, as already described, it is necessary to devise a technique for suppressing the influence of the alignment of one liquid crystal of adjacent pixels on the alignment of the other liquid crystal.

  In the example shown in FIG. 3, the pixel electrode is formed in a comb-teeth shape having a plurality of comb-tooth portions 8a. Specifically, as shown in FIG. 3, the plurality of comb teeth 8 a of the pixel electrode 8 has a strip shape whose longitudinal direction is the y-axis direction in which the video signal line 11 extends, and these comb teeth 8 a They are arranged in the x-axis direction in which the scanning signal lines 10 extend.

  In this case, the direction 17a of the electric field applied to the liquid crystal layer 3 by applying a potential difference between the pixel electrode 8 and the common electrode 9 is mainly the x-axis direction as shown in FIG. 11A. Therefore, in the liquid crystal display panel having such pixels, for example, the alignment direction 18 of the liquid crystal layer 3 when no electric field is applied is inclined by an angle θ from the electric field direction (x-axis direction). The angle θ formed by the alignment direction 18 of the liquid crystal layer 3 and the electric field direction 17a when no electric field is applied is, for example, about 70 to 85 degrees.

  However, as shown in FIG. 11A, in the region (end region) 16 including the end of the pixel electrode 8, the electric field direction 17b is the y-axis direction. Therefore, so-called disclination occurs in the end region 16 of the pixel electrode 8, and this also causes a decrease in transmittance.

  Therefore, in the liquid crystal display device according to the present invention, the polymer structure 7 may be further formed in the end region 16 of the pixel electrode 8. That is, in the example shown in FIG. 11A, the polymer structure 7 is formed in a region straddling the tips of the plurality of comb teeth 8a of the pixel electrode 8.

  FIG. 11B is a cross-sectional view of the end region 16 shown in FIG. 11A. As shown in FIGS. 11A and 11B, the polymer structure 7 is formed so as to straddle the tip portions of the plurality of comb teeth 8 a of the pixel electrode 8 in the end region 16.

  4 shows a main configuration of the color filter substrate 2 facing the TFT substrate 1 shown in FIG. 3 in a plan view. As shown in FIG. 4, on the color filter substrate 2, a black matrix 13 is formed at positions corresponding to the scanning signal lines 10 and the video signal lines 11 shown in FIG. That is, the colored layer 14 of the center pixel PC and the colored layers 14L, 14R, 14U, and 14D of the other adjacent pixels PL, PR, PU, and PD are partitioned by the grid-like black matrix 13.

  5 to 10 are cross-sectional views taken along the line VV in FIG. 5 to 10 are also cross-sectional views taken along the line VV in FIG.

  In the example shown in FIGS. 5A and 5B, the height (thickness) of the black matrix 13 is larger than that of the colored layer 14. In this case, the black matrix 13 is the highest in the color filter substrate 2 even after the alignment film 203 is applied. That is, the portion of the surface of the alignment film 203 that covers the black matrix 13 protrudes into the liquid crystal layer 3.

  5A and 5B, the polymer structure 7 is provided at a position where the black matrix 13 is formed in a convex shape. That is, the polymer structure 7 is formed in a region overlapping with the black matrix 13.

  In FIG. 5A, the cross-sectional shape of the polymer structure 7 is rectangular, but the cross-sectional shape may be trapezoidal as shown in FIG. 5B. Moreover, the tip portion of the polymer structure 7 may be rounded. Further, the density of the polymer structure 7 may be non-uniform. That is, for example, the polymer density of the tip portion of the polymer structure 7 may be smaller than the polymer density of the root portion.

  Further, as shown in FIGS. 5A and 5B, the height of the polymer structure 7 formed on one substrate (color filter substrate 2) reaches the other substrate (TFT substrate 1) facing each other. It does not have to be reached. That is, in this case, the height of the polymer structure 7 is smaller than the thickness of the liquid crystal layer 3. In addition, it can be said that the polymer structure 7 extends to the middle part of the liquid crystal layer 3 from one substrate (color filter substrate 2) to the other substrate (TFT substrate 1).

  The position of the polymer structure 7 is not particularly limited as long as it is between adjacent pixel electrodes 8. The width of the polymer structure 7 is not particularly limited as long as it falls within the range between adjacent pixel electrodes 8. Therefore, as shown in FIG. 6A, the width of the polymer structure 7 may be smaller than the vertical black matrix 13. As shown in FIG. 6C, the width of the polymer structure 7 may be larger than that of the vertical black matrix 13. In addition, as shown in FIG. 6D, the polymer structure 7 may be formed at a position that overlaps with the vertical black matrix 13.

  As shown in FIG. 6B, the polymer structure 7 may be formed along the vertical black matrix and the horizontal black matrix 13. In this case, the polymer structure 7 is formed in a shape surrounding the pixel. That is, a plurality of polymer structures 7 can be formed in parallel with each other between pixel electrodes of adjacent pixels.

  Specifically, FIG. 6A, FIG. 6C, and FIG. 6D show between the pixel electrode of the central pixel PC and the pixel electrode of the adjacent pixel PL on one side (left side), and the pixel electrode of the central pixel PC and the other. Two linear polymer structures 7 which are formed between the pixel electrodes of the adjacent pixels PR on the side (right side) and which are parallel to each other are shown.

  In this case, for example, the color of the central pixel PC and the color of the left pixel PL may be different from each other, and the color of the central pixel PC and the color of the right pixel PR may be different from each other. That is, the polymer structure 7 is formed between pixel electrodes of adjacent pixels having different colors.

  Specifically, for example, in FIGS. 5A and 5B, the polymer structure 7 includes a pixel electrode 8 of a pixel (a central pixel PC shown in FIGS. 6A to 6D) on which a colored layer 14 of a predetermined color is formed, An adjacent pixel (left pixel PL shown in FIGS. 6A to D) formed with a colored layer 14L of a color different from the predetermined color and an adjacent pixel (FIG. 6A) formed with a colored layer 14R of a color different from the predetermined color -D are formed between the pixel electrodes (not shown) of the right pixel PR).

  The polymer structure 7 can also be formed between all adjacent pixel electrodes. Specifically, the polymer structure 7 shown in FIG. 6B includes a pixel electrode 8 of the central pixel PC and all adjacent pixels (left pixel PL, right pixel PR, upper pixel) surrounding the central pixel PC. It is formed in a grid pattern between the pixel electrode of the PU and the lower pixel PD).

  That is, in this case, referring to FIG. 3, the polymer structure 7 includes not only the pixel electrode 8 of the central pixel PC and the pixel electrodes of the left and right adjacent pixels PL and PR, but also the upper and lower adjacent pixels PU. , PD pixel electrodes 8U and 8D are also formed. In this case, one grid-like polymer structure 7 can be formed on the entire liquid crystal display panel.

  In the example shown in FIGS. 5A and 5B, the polymer structure 7 is formed on the color filter substrate 2 side. That is, the polymer structure 7 extends from the color filter substrate 2 into the liquid crystal layer 3.

  On the other hand, in the example shown in FIG. 7, the polymer structure 7 is formed not on the color filter substrate 2 side but on the TFT substrate 1 side. That is, the polymer structure 7 extends from the TFT substrate 1 into the liquid crystal layer 3.

  Thus, the polymer structure 7 is formed only on one of the TFT substrate 1 and the color filter substrate 2.

  In the example shown in FIG. 7, since the insulating layer is provided on the video signal line 11, the video signal line 11 is the highest in the TFT substrate 1 even after the alignment film 103 is applied. A polymer structure 7 having the same width as the convex portion is provided on the convex portion formed on the video signal line 11.

  Also in this case, the polymer structure 7 of the TFT substrate 1 does not need to reach the color filter substrate 2. The position of the polymer structure 7 is not particularly limited as long as it is between adjacent pixel electrodes 8. The width of the polymer structure 7 is not particularly limited as long as it falls within the range between adjacent pixel electrodes 8.

  In the example shown in FIG. 8, the polymer structure 7 may be provided on a flat portion instead of the convex portion of the color filter substrate 2. In this example, the height of the black matrix 13 is equal to or smaller than that of the colored layer 14, and the colored layer 14 is not stacked on the black matrix 13. In this case, a flat color filter substrate 2 is obtained after the alignment film 203 is applied. A polymer structure 7 is provided at a position overlapping with the black matrix 13.

  Also in this case, the polymer structure 7 of the color filter substrate 2 does not have to reach the TFT substrate 1. The position of the polymer structure 7 is not particularly limited as long as it is between adjacent pixel electrodes 8. The width of the polymer structure 7 is not particularly limited as long as it falls within the range between adjacent pixel electrodes 8.

  In the above-described example, the polymer structure 7 is formed on the alignment film (first alignment film 103 or second alignment film 203) of the substrate (TFT substrate 1 or color filter substrate 2). On the other hand, in the example shown in FIG. 9, the polymer structure 7 is formed not on the alignment film 203 of the color filter substrate 2 but on the black matrix 13.

  In this example, in the color filter substrate 2, the height of the black matrix 13 is equal to or smaller than that of the colored layer 14, the colored layer 14 is not stacked on the black matrix 13, and the alignment film 203 is It is not laminated on the black matrix 13 (that is, the alignment film 203 is applied only to the colored layer 14). The polymer structure 7 having a width equal to or smaller than the width of the black matrix 13 is provided directly on the black matrix 13.

  However, the position of the polymer structure 7 is not limited to this as long as it is in the vicinity of the black matrix 13. Further, the width of the polymer structure 7 is not limited to the width of the black matrix 13 or less, and may be larger than the width of the black matrix 13.

  In the example shown in FIG. 10, the color filter substrate 2 does not have the black matrix 13. The polymer structure 7 may be provided in a liquid crystal display device using the color filter substrate 2 that does not have the black matrix 13 as described above.

  In this example, a polymer structure 7 is provided at a position that is a convex portion of the TFT substrate 1. That is, in the TFT substrate 1, the portion of the first alignment film 103 laminated on the video signal line 11 protrudes into the liquid crystal layer 3 to form a convex portion. It is formed along the convex part. Thus, the polymer structure 7 can be formed in a region overlapping with one or both of the scanning signal line 10 and the video signal line 11 regardless of the presence or absence of the black matrix 13.

  Also in this case, the polymer structure 7 of the TFT substrate 1 does not need to reach the color filter substrate 2. The position of the polymer structure 7 is not particularly limited as long as it is between adjacent pixel electrodes 8. The width of the polymer structure 7 is not particularly limited as long as it falls within the range between adjacent pixel electrodes 8. In addition, when the colored layer of the color filter substrate 2 is provided on the TFT substrate 1, the arrangement of the polymer structure 7 as shown in FIG. 10 is preferable.

  In this example, the polymer structure 7 is formed on the TFT substrate 1, but is not limited thereto, and may be formed on the color filter substrate 2. Also in this case, the polymer structure 7 of the color filter substrate 2 does not have to reach the TFT substrate 1. The size of the polymer structure 7 is not particularly limited as long as the polymer structure 7 is in a range including the end region 16 of the pixel electrode 8.

  FIG. 12 shows the formation position of the polymer structure 7 in the liquid crystal display device when a plurality of comb-tooth portions 8 a of the pixel electrode 8 formed in a comb-tooth shape are parallel to the scanning signal line 10. Also in the example shown in FIG. 12, the polymer structure 7 can be formed in the end region 16 that straddles the tip portions of the plurality of comb-tooth portions 8 a of the pixel electrode 8. The formation position of the polymer structure 7 in the pixel is not particularly limited as long as it includes the end region 16 of the pixel electrode 8.

  The liquid crystal layer 3 can also contain a polymer for the purpose of so-called polymer stabilization. That is, in this case, the liquid crystal layer 3 contains a polymer in addition to the polymer structure 7, and the density of the polymer structure 7 is higher than the density of the polymer contained in the liquid crystal layer 3. In the liquid crystal layer 3, a comparatively low density polymer network for stabilizing the polymer is formed, and comparison is made to prevent the influence of the alignment between pixels as described above in a specific region of one substrate. A polymer structure 7 having a large target density is formed.

  In the present invention, as a method of forming the polymer structure 7, a method of forming the polymer structure 7 by polymerizing a polymerizable monomer contained in the liquid crystal composition is preferably used. That is, in this case, the method for manufacturing a liquid crystal display device according to the present invention includes a step of enclosing the liquid crystal layer 3 between the first substrate (TFT substrate 1) and the second substrate (color filter substrate 2). In this step, a liquid crystal composition obtained by adding a polymerizable monomer to the base liquid crystal used for the liquid crystal layer 3 is sealed between the first substrate and the second substrate, and the adjacent pixel electrode 8 A polymerization initiator is localized between them, and then the polymerizable monomer is polymerized to form the polymer structure 7 between the adjacent pixel electrodes 8.

  The liquid crystal layer 3 is a liquid crystal composition composed of a liquid crystal material and several kinds of additives. In this liquid crystal composition, the content of the polymerizable monomer used for forming the polymer structure 7 (ratio of the polymerizable monomer in the total weight of the liquid crystal composition constituting the liquid crystal layer 3) is, for example, 2.0 wt. % Or less, preferably 1.5% by weight or less.

  At this time, the content of the polymerizable monomer is more preferably 1.0% by weight or less. However, 0.5% by weight or more is necessary to obtain the effect of the present invention. The content of the polymer structure 7 finally formed in the liquid crystal display device in the liquid crystal layer 3 is similarly in the range of 0.5 wt% to 2.0 wt%.

  In this case, the content of the liquid crystal material in the liquid crystal layer 3 (the ratio of the liquid crystal material to the total weight of the liquid crystal composition constituting the liquid crystal layer 3) can be, for example, 98.0 to 99.0% by weight. . Note that a nematic liquid crystal material can be preferably used as the liquid crystal material contained in the liquid crystal composition.

  When polymerizing the polymerizable monomer contained in the liquid crystal layer 3 to form the polymer structure 7, the liquid crystal composition containing the polymerizable monomer is sealed between the TFT substrate 1 and the color filter substrate 2, Next, the polymer structure 7 is formed by polymerizing the polymerizable monomer in the sealed liquid crystal composition.

  Here, as the polymerizable monomer, for example, a photopolymerizable monomer that is polymerized by irradiation with light can be preferably used. That is, for example, a photopolymerizable monomer having two or more functional groups can be preferably used. Specifically, a derivative having one or both of an acrylic group and a methacryl group as functional groups at both ends of the main skeleton structure containing an aromatic ring can be preferably used.

  Moreover, for the formation of the polymer structure 7, for example, a liquid crystalline polymerizable monomer can be used. In this case, the liquid crystal material includes a base liquid crystal and a liquid crystalline polymerizable monomer. By using a polymerizable monomer exhibiting liquid crystallinity, the effect of stabilizing the liquid crystal material with the polymer structure 7 can be enhanced. As the polymerizable monomer, one of these can be used alone, or two or more can be used in combination.

  When the photopolymerizable monomer is used, the polymer structure 7 irradiates the liquid crystal composition sealed between the TFT substrate 1 and the color filter substrate 2 with light satisfying a predetermined condition, and applies the liquid crystal composition to the liquid crystal composition. It is formed by polymerizing the contained photopolymerizable monomer.

  That is, first, a TFT substrate 1 and a color filter substrate 2, and a liquid crystal composition containing a liquid crystal material and a photopolymerizable monomer are prepared. Next, the TFT substrate 1 and the color filter substrate 2 are bonded together, and a liquid crystal composition is sealed between the TFT substrate 1 and the color filter substrate 2.

  Moreover, when polymerizing a photopolymerizable monomer, it is preferable to use a photopolymerization initiator. The photopolymerization initiator is not particularly limited as long as it allows the polymerization of the photopolymerizable monomer to proceed effectively with light irradiation to the liquid crystal composition, and any kind of photopolymerization initiator may be appropriately selected and used. it can. That is, for example, a photopolymerization initiator that generates free radicals by irradiation of ultraviolet rays and effectively promotes radical polymerization of the photopolymerizable monomer can be preferably used.

  Examples of the photopolymerization initiator include 9-fluorenone, 1-hydroxycyclohexyl-phenyl ketone, dibenzosuberone, 2-hydroxy-2-methylpropiophenone, benzoin, 2-benzoylbenzoic acid, 4-benzoylbenzoic acid, 2,2-diethoxyacetophenone, benzoin isobutyl ether, benzoin isopropyl ether, acetophenone, 2,2-diethoxyphenyl-acetophenone, benzoin ethyl ether, benzoin methyl ether, camphorquinone, 2,2-dimethoxy-2-phenylacetophenone, 2-chlorobenzophenone, 2-ethylanthraquinone, 4,4'-dichlorobenzophenone, 4-chlorobenzophenone, benzyl, benzophenone, methyl-2-benzoylbenzoate p- anisyl can be used.

  In the present invention, a thermal polymerization initiator can also be preferably used. Examples of the thermal polymerization initiator include 2,2-azobisisobutyronitrile (AIBN). Moreover, since the high molecular weight body of AIBN is also commercialized, these can be used.

  In addition, when the polymerization initiator is localized in a specific region of the alignment film by using adsorption of the polymerization initiator to the alignment film as described later, polymerization with a large adsorptivity to the specific region of the alignment film is performed. Initiators are preferred. That is, for example, when the liquid crystal display device has a highly polar alignment film, it is preferable to use a polymerization initiator having a large polarity. The polymerization initiator may be a low molecule or a polymer.

  Further, when the polymer structure 7 is formed by polymerizing the polymerizable monomer contained in the liquid crystal composition, the first alignment film 103 and the second alignment film 203 are liquid crystal materials contained in the liquid crystal layer 3. The alignment film is not particularly limited as long as it can be effectively aligned. For example, an alignment film made of polyimide and subjected to appropriate alignment treatment can be preferably used. Specifically, for example, an alignment film made of polyimide formed from 1,3-dimethyl-cyclobutanetetracarboxylic dianhydride and aromatic diamine can be used.

  In order to form the polymer structure 7 in a specific region between the pair of substrates 1 and 2 bonded together, it is common to perform mask exposure using an ultraviolet exposure device. Alignment is difficult and productivity decreases. However, the mask exposure for a single substrate (substrate not bonded to another substrate) such as the TFT substrate 1 or the color filter substrate 2 means exposure to a liquid crystal panel having the above-mentioned pair of bonded substrates. In comparison, it is advantageous in terms of process and cost.

  In the present invention, the polymer structure 7 is formed in a specific region between the TFT substrate 1 and the color filter substrate 2 on the premise that the entire surface is exposed, not the mask exposure (partial exposure), by the ultraviolet exposure apparatus. Use the method. That is, by localizing the polymerization initiator in a specific region between adjacent pixel electrodes 8, the polymer structure 7 is selectively formed in the specific region by overall exposure.

  As a first method, a polymerization initiator is applied to a specific region between adjacent pixel electrodes 8 on one of the first substrate (TFT substrate 1) and the second substrate (color filter substrate 2). By applying in advance, the polymerization initiator is localized between the adjacent pixel electrodes 8.

  Then, the polymer structure 7 is selectively formed in the specific region by the entire surface exposure on the TFT substrate 1 or the color filter substrate 2 on which the polymerization initiator is selectively applied to the specific region in advance.

  For example, if ink jet printing is used, the polymerization initiator can be applied to any position of the color filter substrate, so that the polymer structure 7 having the shape shown in FIGS. 5 to 8 can be formed. Further, for example, if reverse printing is used, a polymerization initiator can be applied in advance to the convex portions of the TFT substrate 1 or the color filter substrate 2, so that the polymer structure 7 having the shape shown in FIG. 5 or FIG. Can be formed. By this method, the polymerization initiator can be further localized in the end region 16 of the pixel electrode 8.

  As a second method on the premise that the entire surface is exposed by the ultraviolet exposure apparatus, the pixel electrode 8 adjacent to one of the first substrate (TFT substrate 1) and the second substrate (color filter substrate 2) is used. The polymerization initiator is localized between the adjacent pixel electrodes 8 by making the surface energy of the specific region corresponding to between different the surface energy of the region other than the specific region.

  That is, for example, a surface treatment is performed in advance so that the polymerization initiator is easily adsorbed to a specific region of the TFT substrate 1 or the color filter substrate 2. As the surface treatment, for example, a specific region of the alignment film (for example, a region corresponding to the black matrix 13, a region corresponding to the scanning signal line 10 and / or the video signal line 11 in the surface of the alignment film, etc.) by mask exposure. By irradiating the region corresponding to the boundary portion of the pixel electrode 8 and the end region 16) of the pixel electrode 8 with ultraviolet rays, the surface energy of the specific region is made larger than the surface energy of the portion other than the specific region. A process to do is conceivable.

  In this way, the polymerization initiator contained in the liquid crystal composition sealed between the TFT substrate 1 and the color filter substrate 2 can be localized in the specific region and the vicinity thereof. That is, after the liquid crystal composition is sealed between the TFT substrate 1 and the color filter substrate 2, the polymerization initiator contained in the liquid crystal composition is in a specific region having a surface energy larger than that of other regions and in the vicinity thereof. Will be localized.

  Then, the entire surface of the TFT substrate 1 or the color filter substrate 2 is exposed in a state where the polymerization initiator is localized in the specific region, whereby the polymer structure having the shape shown in FIGS. 5 to 8 is formed in the specific region. Objects 7 can be selectively formed. By this method, the polymerization initiator can be further localized in the end region 16 of the pixel electrode 8.

  As a third method based on the premise that the entire surface is exposed by the ultraviolet exposure apparatus, there is a method using a light shielding portion of the TFT substrate 1 or the color filter substrate 2. That is, for example, the black matrix 13 of the color filter substrate 2 is used as a light shielding portion.

  Specifically, for example, first, a photopolymerization initiator is applied to the entire surface of the alignment film 203 of the color filter substrate 2, and then from the insulating substrate 201 side of the color filter substrate 2 through the black matrix 13. The surface of the alignment film 203 is irradiated with ultraviolet rays.

  As a result, only the photopolymerization initiator on the black matrix 13 of the photopolymerization initiator coated with the alignment film 203 remains without being deactivated. That is, the photopolymerization initiator can be localized in a specific region corresponding to the black matrix 13.

  Of course, the photopolymerization initiator was applied to the entire surface of the alignment film 203, and then mask exposure from the surface side of the alignment film 203 was applied to a portion of the surface other than the specific region. The photopolymerization initiator may be deactivated. By this method, the polymerization initiator can be further localized in the end region 16 of the pixel electrode 8.

  In the above example, it is assumed that the entire surface is exposed by the ultraviolet exposure apparatus, but this is not the case when a thermal polymerization initiator is used. That is, when a thermal polymerization initiator is used, for example, by heating the entire liquid crystal display device, the polymer structure 7 is selected in specific regions such as between the pixel electrodes of the liquid crystal display device and the end regions of the pixel electrodes. Can be formed.

  Thus, in the method for manufacturing a liquid crystal display device according to the present invention, the polymerization initiator is localized in a specific region of one of the TFT substrate 1 and the color filter substrate 2, and the specific region of the one substrate is To polymerize the polymerizable monomer preferentially to form the polymer structure 7. Therefore, according to the present invention, it is possible to provide a liquid crystal display device having high transmittance and high productivity efficiency and a method for manufacturing the same.

  In addition to the formation of the polymer structure 7, a polymerizable monomer may be added to the liquid crystal composition for the purpose of so-called polymer stabilization. In this case, the liquid crystal layer 3 contains a polymer in addition to the polymer structure 7, and the density of the polymer structure 7 is higher than the density of the polymer contained in the liquid crystal layer 3.

  That is, in the liquid crystal layer 3, a polymer network having a relatively low density for polymer stabilization is formed, and the polymer structure 7 as described above is formed in a specific region of one substrate. Will be.

  Next, specific examples of the liquid crystal display panel according to the present invention will be described.

  In Example 1, a specific formation method and operation effect when the polymer structure 7 is provided in an FFS mode liquid crystal display panel which is one of IPS modes will be described.

  In Example 1, a liquid crystal display panel having a planar dimension of 100 mm (long piece side) × 100 mm (short piece side) and a diagonal dimension of about 6 inches was manufactured. The thickness of this liquid crystal display panel was 1.1 mm. The size of one pixel (Py × Px) was 600 μm × 200 μm. As the first insulating substrate 101 and the second insulating substrate 201 in this liquid crystal display panel, transparent glass substrates whose surfaces were polished were used.

  A first thin film having a scanning signal line, a video signal line, a TFT element, a pixel electrode, a common electrode, and an insulating layer as shown in FIG. A stacked body 102 and a first alignment film 103 were formed to obtain a TFT substrate 1. The width of the short side of the common electrode was 160 μm, the number of pixel electrodes was four, the lines and spaces were 20 μm, and the width of the entire pixel electrode was 140 μm.

  On the second insulating substrate 201 which is the other glass substrate, a second thin film laminate 202 having a black matrix, a colored layer and a planarizing layer and a second alignment film 203 are formed, and a color filter substrate 2. The width of the black matrix was 40 μm.

  At this time, polyimide was adopted as a material constituting the first alignment film 103 and the second alignment film 203. That is, first, a polyimide resin precursor was applied by a printing machine and baked to form a polyimide film having a thickness of 0.07 to 0.1 μm.

  Thereafter, an alignment treatment for aligning the liquid crystal material included in the liquid crystal layer 3 was performed on the surface of the polyimide film to form the first alignment film 103 and the second alignment film 203. The orientation treatment was performed using a rubbing machine equipped with a rayon buff cloth as a rubbing roll. The rubbing angle was set to 15 degrees with respect to the comb tooth direction of the pixel electrode so as to be parallel between the pair of substrates 1 and 2.

  Next, as shown in FIG. 5, the convex portion of the alignment film on the black matrix 13 on the video signal line 11 of the color filter substrate 2 on which the polyimide film is formed hardly dissolves in the liquid crystal as a polymerization initiator. A 1 wt% ethanol solution in which 2-hydroxy-2-methylpropiophenone (Darocur 1173, Nagase Sangyo Co., Ltd.) was dissolved was applied by an inkjet method. Thereafter, ethanol was air-dried to obtain a color filter substrate 2.

  Adhesion between the TFT substrate 1 and the color filter substrate 2 was performed via the annular sealing material 4a shown in FIG. That is, a composite sealant was prepared by mixing an appropriate amount of polymer beads into a sealant made of epoxy resin, and the sealant 4a was formed by printing the composite sealant on one substrate using a seal mask. Then, the composite sealing agent which comprises the sealing material 4a was temporarily hardened, and the TFT substrate 1 and the color filter substrate 2 were combined. And the sealing material 4a was fully hardened, pressing the said pair of board | substrate using a press.

  At this time, a gap (thickness d) in a state where a spherical polymer bead is sandwiched in a space (panel portion) surrounded by the TFT substrate 1, the color filter substrate 2, and the sealing material 4a and a liquid crystal composition is sealed. ) Was adjusted to 4.5 μm. At this time, the width of the liquid crystal injection port provided in the sealing material 4a for injecting the liquid crystal composition into the panel portion was set to 10 mm.

  Meanwhile, a liquid crystal composition A composed of a polymerizable monomer, a polymerization initiator, and a liquid crystal material was prepared as a liquid crystal composition used for forming the liquid crystal layer 3 and the polymer structure 7. As the polymerizable monomer, a bifunctional acrylic monomer was used. As the polymerization initiator, 2,2-diethoxyphenyl-acetophenone (Irgacure 651, Nagase Sangyo Co., Ltd.) that dissolves in liquid crystal was used. As the liquid crystal material, a fluorine-based nematic liquid crystal composition was used. The weight ratios of the polymerizable monomer, the polymerization initiator, and the liquid crystal material in the liquid crystal composition A were 1.2% by weight, 0.1% by weight, and 98.7% by weight, respectively.

  Next, the liquid crystal composition A was injected into the space surrounded by the TFT substrate 1, the color filter substrate 2, and the sealing material 4a. That is, the liquid crystal display panel was placed in a sealable container (not shown) with the liquid crystal inlet facing downward. In addition, the liquid crystal composition A was put in a liquid crystal dish connected to a vertical drive device provided outside the container. The liquid crystal composition A was held in a slightly raised state in the liquid crystal dish.

  A pipe connected to a vacuum pump and a Pirani gauge was provided outside the container. Then, the vacuum pump was operated, the exhaust amount was adjusted while monitoring the Pirani gauge with the adjusting valve, and the inside of the container was decompressed until the degree of vacuum reached 5 Pa in 120 minutes.

  Next, the vertical driving device was operated to immerse the liquid crystal injection port in the liquid crystal composition A. Thereafter, the adjustment valve is closed, the adjustment valve of the leak pipe is opened, nitrogen or air is introduced into the container, and the liquid crystal composition A is placed in the space surrounded by the TFT substrate 1, the color filter substrate 2, and the sealing material 4a. Injected. After the injection was completed, the liquid crystal injection port was sealed with a sealing material 4b made of an ultraviolet curing agent (acrylic resin).

  Then, the polymer stabilization process which superposes | polymerizes a polymerizable monomer in a liquid crystal composition was implemented by irradiating an ultraviolet-ray from the TFT substrate 1 side. Thus, a liquid crystal display panel having the liquid crystal layer 3 and the polymer structure 7 formed using the liquid crystal composition A was produced.

  Three comparative panels were prepared. In the comparative panel A, only the electrode configuration was changed, and the other configurations were not changed. The electrode configuration of this comparative panel A was as follows. That is, the width of the short side of the common electrode was 120 μm, the number of pixel electrodes was 3, the line and space were 20 μm, and the width of the entire pixel electrode was 100 μm.

  For the comparative panel B, only the ultraviolet irradiation condition and the rubbing angle were changed, and the other configurations were not changed. In the comparative panel B, ultraviolet rays were not irradiated, and the rubbing angle was set to 60 degrees with respect to the comb tooth direction of the pixel electrode so as to be parallel between the pair of substrates 1 and 2.

  For the comparative panel C, only the ultraviolet irradiation conditions were changed, and the other configurations were not changed. In the comparative panel C, the step of irradiating ultraviolet rays was not performed.

  And the transmittance | permeability in the liquid crystal display panel and comparison panel which were manufactured in this way was evaluated. The transmittance was evaluated by the ratio of incident light and outgoing light. In this example, since the liquid crystal alignment giving the maximum transmittance was realized in the comparative panel B, the transmittance of the liquid crystal display panel and the comparative panel of this example was calculated with the comparative panel B as 100%.

  As a result, the transmittance of the liquid crystal display panel was 65%, and the transmittance of the comparative panel B was 50%. Therefore, the transmittance of the liquid crystal display panel of this example was improved by 15% compared with the comparative panel. In this example, only the blue pixels of the liquid crystal display panel were driven, but there was no color leakage of red and green pixels, and no influence of liquid crystal alignment between adjacent pixels was observed. On the other hand, when only the blue pixels were driven in the comparative panel C, color leakage of red and green pixels was observed. Therefore, in the comparative panel C, it was confirmed that the influence of liquid crystal alignment was produced between adjacent pixels.

  Next, after disassembling the liquid crystal display panel, the liquid crystal composition A in the liquid crystal display panel was washed away with benzene. Thereafter, the liquid crystal display panel was cooled to 0 ° C. with benzene in place, and the benzene was removed by freeze drying. And the cross section of the liquid crystal display panel after removing this benzene was observed with the electron microscope.

  As a result, as shown in FIG. 5, the polymer structure 7 was observed on the video signal line 11 of the color filter substrate 2 and below the black matrix 13 at a position overlapping the black matrix 13. Therefore, it was considered that the presence of the polymer structure 7 eliminated the influence of liquid crystal alignment between adjacent pixels when the liquid crystal display panel was driven. In this embodiment, since the concentration of the polymerization initiator is the highest on the black matrix 13 on the video signal line 11, the polymer structure 7 is selectively formed on the black matrix 13 on the video signal line 11. it was thought.

  In this example, a photopolymerization initiator was used. However, it is clear that the same effect can be obtained even if a thermal polymerization initiator is applied on the black matrix 13 in advance. It is also clear that the same effect can be obtained by applying in advance a specific material such as a polymer material that is easily adsorbed by the polymerization initiator instead of the photopolymerization initiator.

  In this embodiment, the polymer structure 7 is formed on the convex portions on the black matrix 13 of the color filter substrate 2 as shown in FIG. 5, but on the video signal line 11 of the TFT substrate 1 as shown in FIG. Even if the polymer structure 7 is formed on the convex portion, the same effect can be obtained. Further, although the polymerization initiator is applied by the ink jet method, it may be applied by reverse printing.

  In Example 2, a polymerization initiator was applied on the black matrix 13 of the color filter substrate 2 as in Example 1. At this time, a 1 wt% ethanol solution in which 2-hydroxy-2-methylpropiophenone (Darocur 1173, Nagase Sangyo Co., Ltd.), which is difficult to dissolve in the liquid crystal as a polymerization initiator, is applied to the entire color filter substrate 2 by the inkjet method. did. Thereafter, ultraviolet rays were irradiated from the insulating substrate 201 side to deactivate the polymerization initiator other than the polymerization initiator applied on the black matrix 13. In the second embodiment, since the same method as that of the first embodiment is used except for these substrate treatments, description on the manufacturing procedure of the liquid crystal display panel is omitted.

  The transmittance of the thus manufactured liquid crystal display panel and comparative panel was evaluated. As a result, the transmittance of the liquid crystal display panel was improved by 15% or more than the comparative panel. Moreover, although only the blue pixel of the liquid crystal display panel was driven, there was no color leakage of the red and green pixels, and the influence of the liquid crystal alignment between adjacent ones was not seen.

  Next, after disassembling the liquid crystal display panel, the liquid crystal composition A in the liquid crystal display panel was washed away with benzene. Thereafter, the liquid crystal display panel was cooled to 0 ° C. with benzene in place, and the benzene was removed by freeze drying. And the cross section of the liquid crystal display panel after removing this benzene was observed with the electron microscope.

  As a result, as shown in FIG. 8, a polymer structure 7 having a width substantially the same as the width of the black matrix 13 was observed under the black matrix 13 on the video signal line 11 of the color filter substrate 2. Therefore, it was considered that the presence of the polymer structure 7 eliminated the influence of liquid crystal alignment between adjacent pixels when the liquid crystal display panel was driven. In this embodiment, since the concentration of the polymerization initiator is the highest on the black matrix 13 on the video signal line 11, the polymer structure 7 is selectively formed on the black matrix 13 on the video signal line 11. it was thought.

  In Example 3, as in Examples 1 and 2, the polymerization initiator was not applied on the TFT substrate 1 or the color filter substrate 2 in advance. However, as shown in FIG. 9, the color filter substrate 2 in which the colored layer 14 and the alignment film were not applied on the black matrix 13 was used. In Example 3, since the same method as that in Example 1 was used except for these substrate treatments, description on the manufacturing procedure of the liquid crystal display panel was omitted.

  The transmittance of the thus manufactured liquid crystal display panel and comparative panel was evaluated. As a result, the transmittance of the liquid crystal display panel was improved by 15% or more than the comparative panel. Moreover, although only the blue pixel of the liquid crystal display panel was driven, there was no color leakage of the red and green pixels, and the influence of the liquid crystal alignment between adjacent ones was not seen.

  Next, after disassembling the liquid crystal display panel, the liquid crystal composition A in the liquid crystal display panel was washed away with benzene. Thereafter, the liquid crystal display panel was cooled to 0 ° C. with benzene in place, and the benzene was removed by freeze drying. And the cross section of the liquid crystal display panel after removing this benzene was observed with the electron microscope.

  As a result, as shown in FIG. 9, a polymer structure 7 having a width substantially the same as the width of the black matrix 13 was observed under the black matrix 13 of the color filter substrate 2. Therefore, in this example, it was considered that the polymerization initiator was selectively adsorbed on the black matrix 13 and thus the polymer structure 7 was formed to overlap the black matrix 13. As a result, the presence of the polymer structure 7 was considered to have eliminated the influence of liquid crystal alignment between adjacent pixels when the liquid crystal display panel was driven.

  Also in Example 4, like Example 1 and Example 2, the application | coating process of the polymerization initiator was not implemented on the TFT substrate 1 or the color filter substrate 2 previously. However, as shown in FIG. 10, by selectively irradiating the specific region corresponding to the video signal line 11 on the surface of the alignment film 103 of the TFT substrate 1, the polarity of the specific region becomes the alignment layer. A TFT substrate 1 having a height higher than that of the other region of the film 103 was produced. In Example 4, since the same method as that in Example 1 was used except for these substrate treatments, description on the manufacturing procedure of the liquid crystal display panel was omitted.

  The transmittance of the thus manufactured liquid crystal display panel and comparative panel was evaluated. As a result, the transmittance of the liquid crystal display panel was improved by 15% or more than the comparative panel. Moreover, although only the blue pixel of the liquid crystal display panel was driven, there was no color leakage of the red and green pixels, and the influence of the liquid crystal alignment between adjacent ones was not seen.

  Next, after disassembling the liquid crystal display panel, the liquid crystal composition A in the liquid crystal display panel was washed away with benzene. Thereafter, the liquid crystal display panel was cooled to 0 ° C. with benzene in place, and the benzene was removed by freeze drying. And the cross section of the liquid crystal display panel after removing this benzene was observed with the electron microscope.

  As a result, as shown in FIG. 10, the polymer structure 7 having the same width as the specific region was observed on the specific region of the TFT substrate 1. Therefore, it was considered that the presence of the polymer structure 7 eliminated the influence of liquid crystal alignment between adjacent pixels when the liquid crystal display panel was driven. In this example, it was considered that the polymer structure 7 was selectively formed on the specific region as a result of the selective adsorption of the polymerization initiator on the specific region.

  In this embodiment, ultraviolet light is irradiated to a portion on a specific region of the alignment film 103, but an alignment film having a higher polarity than other portions of the alignment film 103 may be applied to the portion on the specific region. Obviously, similar effects can be obtained.

  In Example 5, as shown in FIG. 11A, in the alignment film 203 on the color filter substrate 2, the end region 16 of the pixel electrode 8 is irradiated with ultraviolet rays, and the polarity of the end region 16 is different from that of other regions. A raised color filter substrate 2 was produced. In Example 5, since the same method as that in Example 1 was used except for these substrate treatments, description on the manufacturing procedure of the liquid crystal display panel was omitted.

  The transmittance of the thus manufactured liquid crystal display panel and comparative panel was evaluated. As a result, the transmittance of the liquid crystal display panel was comparable to that of the comparative panel. However, when the liquid crystal display panel was driven, the liquid crystal in the end region 16 of the pixel electrode 8 did not respond to the electric field, and the occurrence of disclination was not observed. I couldn't.

  Next, after disassembling the liquid crystal display panel, the liquid crystal composition A in the liquid crystal display panel was washed away with benzene. Thereafter, the liquid crystal display panel was cooled to 0 ° C. with benzene in place, and the benzene was removed by freeze drying. And the cross section of the liquid crystal display panel after removing this benzene was observed with the electron microscope.

  As a result, as shown in FIG. 11B, the polymer structure 7 was observed in the end region 16 of the pixel electrode 8 in the alignment film 203 of the color filter substrate 2. Therefore, it was considered that due to the presence of the polymer structure 7, the liquid crystal in the end region 16 did not respond to an electric field when the liquid crystal display panel was driven, and no disclination occurred. In this example, it was considered that the polymer structure 7 was selectively formed in the portion of the alignment film as a result of the selective adsorption of the polymerization initiator to the portion irradiated with ultraviolet rays in advance.

  The present invention has been specifically described above based on the above-described embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Of course.

  Further, even when the liquid crystal layer 3 is formed by encapsulating the liquid crystal composition by ODF (drop encapsulation) instead of vacuum encapsulation, the liquid crystal is also excellent in transmittance and reliability. A display panel (liquid crystal display device) can be provided.

  DESCRIPTION OF SYMBOLS 1 TFT substrate, 101 1st insulating substrate, 102 1st thin film laminated body, 103 1st orientation film, 2 Color filter substrate, 201 2nd insulating substrate, 202 2nd thin film laminated body, 203 2nd Alignment film, 3 liquid crystal layer, 4a, 4b sealing material, 5 first polarizing plate, 6 second polarizing plate, 7 polymer structure, 8, 8U, 8D pixel electrode, 8a comb tooth portion, 9 common electrode, 10 scanning signal line, 11 video signal line, 12 TFT element, 13 black matrix, 14, 14L, 14R, 14U, 14D colored layer, 16 end region, 17a, 17b electric field direction, 18 pretilt direction, PC, PL, PR , PU, PD pixels.

Claims (18)

A first substrate, a second substrate, and a liquid crystal layer sealed between the first substrate and the second substrate, wherein one of the first electrode and the second electrode is a pixel electrode A liquid crystal display device provided with a plurality of pixels having two electrodes,
The first electrode and the second electrode are provided on one of the first substrate and the second substrate,
A liquid crystal display device, wherein a polymer structure is formed between adjacent pixel electrodes. The liquid crystal display device according to claim 1, wherein the polymer structure is formed between the pixel electrodes of adjacent pixels having different colors. A color filter is formed on one of the first substrate and the second substrate, and the polymer structure is formed on the one substrate on which the color filter is formed. The liquid crystal display device according to claim 1 or 2. The liquid crystal display device according to claim 3, wherein the polymer structure is formed in a region overlapping with a black matrix. The liquid crystal display device according to claim 1, wherein the polymer structure is formed on the one substrate side on which the pair of electrodes are formed. The liquid crystal display device according to claim 5, wherein the polymer structure is formed in a region overlapping with one or both of a scanning signal line and a video signal line. The liquid crystal display device according to claim 1, wherein the polymer structure is further formed in a region including an end portion of the pixel electrode. The liquid crystal layer contains a polymer in addition to the polymer structure,
The liquid crystal display device according to claim 1, wherein a density of the polymer structure is higher than a density of the polymer contained in the liquid crystal layer. The liquid crystal display device according to claim 1, wherein the polymer structure is formed by polymerizing a polymerizable monomer in the liquid crystal layer. The liquid crystal display device according to claim 9, wherein the polymer structure is formed by polymerizing a polymer precursor in the presence of a photopolymerization initiator in the liquid crystal layer. The liquid crystal display device according to claim 9, wherein the polymer structure is formed by polymerizing a polymer precursor in the presence of a thermal polymerization initiator in the liquid crystal layer. Manufacture of a liquid crystal display device having a liquid crystal layer sealed between a first substrate and a second substrate, and a plurality of pixels each having a first electrode and a second electrode, each of which is a pixel electrode A method,
Encapsulating the liquid crystal layer between the first substrate and the second substrate;
In the step, a liquid crystal composition containing a base liquid crystal and a polymerizable monomer used for the liquid crystal layer is sealed between the first substrate and the second substrate, and is polymerized between the adjacent pixel electrodes. A method of manufacturing a liquid crystal display device, wherein an initiator is localized, and then the polymerizable monomer is polymerized to form a polymer structure between adjacent pixel electrodes. The method for producing a liquid crystal display device according to claim 12, wherein the liquid crystal composition includes the polymerization initiator. The method for producing a liquid crystal display device according to claim 13, wherein the polymerization initiator is a photopolymerization initiator. The method for producing a liquid crystal display device according to claim 13, wherein the polymerization initiator is a thermal polymerization initiator. Of the first substrate and the second substrate, the polymerization initiator is adjacently applied by pre-applying the polymerization initiator to a corresponding region between the adjacent pixel electrodes of one substrate. The method for manufacturing a liquid crystal display device according to claim 12, wherein the liquid crystal display device is localized between the pixel electrodes. Of the first substrate and the second substrate, the surface energy of the specific region corresponding to the area between the adjacent pixel electrodes on one substrate is different from the surface energy of the region other than the specific region. The method of manufacturing a liquid crystal display device according to claim 12, wherein the polymerization initiator is localized between the adjacent pixel electrodes. The method for manufacturing a liquid crystal display device according to claim 12, wherein the polymerization initiator is further localized in a region corresponding to an end portion of the pixel electrode.

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